1. Field of the Invention
The present invention relates to a micro spike which is a biopsy tool used to pick a tissue, and more particularly to a micro spike having a three-dimensional structure made of a single crystalline silicon and being capable of picking an enough amount of a tissue to examine the tissue while minimizing an examinee's pain with a minimal invasion when picking the tissue, and a method of manufacturing the same.
2. Description of the Prior Art
In the medical area, biopsy tools are essential in preparing tissue samples for pathological tests. However, since a conventional biopsy tool according to the prior art has a relatively big size, an amount of the extracted tissue samples is unnecessarily much and it causes significant discomfort, risk, and injury to the patients. However, since a biopsy tool according to the prior art has a relatively big size, an amount of a tissue picked is unnecessarily much when picking the tissue. In addition, it is required many amounts of reagents to analyze the sampled tissue and the patient should endure pain and risk resulting from the medical treatment.
For solving the above problems, there are suggested micro biopsy/precision cutting devices having a relatively small size, which are made by applying a micro machining process and a precision process. However, since most of the micro biopsy tools or precision cutting devices having a small size have a complex structure, it is difficult to manipulate the device when performing the biopsy and thus a skillful operator is required.
FIG. 1 shows a catheter used to pick a tissue sample according to the prior art. As shown, the catheter comprises forceps jaws 202, a micro needle 204 and a main body 201.
The catheter 200 shown in FIG. 1 has a structure such that the micro needle 204 having an jagged structure is mounted to a center of the catheter and the forceps jaws 202 are mounted to both sides of the needle. The catheter 200 of FIG. 1 picks a tissue such a manner that a surface of the tissue is stretched when pricking and drawing the tissue 500 with the micro needle 204 and then the forceps jaws 202 pick up and separate the stretched tissue. The catheter has an advantage of securing an accurate picking amount when picking the tissue.
However, when picking the tissue using the catheter 200 of FIG. 1, since two processes of pricking the tissue with the micro needle 204, and picking and separating the tissue with the forceps jaws 202 should be performed, an examinee's pain is increased. In addition, there is an inconvenience that a movement of forceps jaws 202 should be manipulated to separate the tissue under state that the tissue is stretched with the micro needle 204.
Additionally, according to the catheter 200 shown in FIG. 1, since the main body 201, the micro needle 204 and the forceps jaws 202 are integrated, the main body part 201 as well as the micro needle 204 and the forceps jaws 202 should be discarded after the catheter 200 is once used for the tissue picking. In other words, since the prior catheter is disposable, it is not desirable from a point of view of an efficient use of resources.
In the mean time, there are known methods using a substrate bonding, a LIGA (Lithographic, Galvanoformung, Abformung) process, and a laser micro machining process for manufacturing a three-dimensional micro device. Hereinafter, each of the methods will be briefly described.
The substrate bonding method is such that a structure is respectively formed on two substrates and then the two substrates are bonded to form a three-dimensional structure at a last step. According to this method, it is difficult to bond the substrates and there is much possibility of the structure to be transformed due to stress between the two substrates.
The LIGA method is such that a photographing process is performed on a thick photoresist using an ion beam such as ultraviolet or X-ray emitting from a particle accelerator, a gap between the photoresist remaining after development is filled up by an electroplating method, and then a metal mold box for molding is formed.
A three-dimensional LIGA process is a method of manufacturing a three-dimensional structure by performing an exposure process while rotating the ion beam to several directions. This method has a disadvantage such that it is difficult to obtain equipment capable of exposing the ion beam since the equipment is very expensive. In addition, since the three-dimensional structure made according to the LIGA process is hard to plate a photoresist structure after the exposure, it is impossible to make the molding box. Further, since the biopsy devise of the three-dimensional structure consisting of the photoresist material only has very low durability, it is impossible to virtually use it for the biopsy.
Since the laser micro machining method processes an arbitrary shape in a manner of scanning the shape with the laser so as to make the shape, it takes much time to manufacture it. In addition, since a manufacturing cost is high, there is a difficulty in the mass-production.
As described above, according to the prior methods of manufacturing the micro device, there are many difficulties such as a complex manufacturing process, a requirement of expensive manufacturing equipment, and a low durability of the micro device. Accordingly, there is a need of a method capable of manufacturing a three-dimensional biopsy tool having a firm structure while easily manufacturing it. In addition, as described above, there is needed a biopsy tool which is capable of minimizing a risk and a patient's pain when picking the tissue and which can be handled easily.
A technology concerning transcorneal drug-release system and a micropin is disclosed in U.S. Pat. No. 6,132,755. Said transcorneal drug-release system and micropin are devices for injecting the drug into the skin, manufactured by sintering in a mould (col. 4 lines 12-15). The device is attached or fixed onto the skin like plaster or a wristwatch and cannot be inserted into the body. Therefore, said transcorneal drug-release system only injects drug into the skin and make the drug penetrate the Stratum corneum. Said transcorneal drug-release system is unable to pick tissue of an organ in the body or inject drug into a specific organ in the body.